Treatment of functional gastrointestinal disorders with antidepressant medications: a meta-analysis

BACKGROUND: Functional gastrointestinal disorders are common, accounting for up to 50% of gastroenterology referrals, and several randomized controlled trials have evaluated antidepressant therapy for their treatment. METHODS: We performed a meta-analysis of published, English-language, randomized clinical trials on the use of antidepressants for the treatment of patients with functional gastrointestinal disorders. RESULTS: Twelve randomized placebo-controlled trials of antidepressant treatment of functional gastrointestinal disorders were identified. One was excluded for using a combination of a tricyclic and neuroleptic agent. The medications included tricyclic antidepressants (amitriptyline [n = 3], clomipramine [n = 1], desipramine [n = 2], doxepin [n = 1], and trimipramine [n = 2]), and the antiserotonin agent, mianserin (n = 2). In addition, one trial compared two different antidepressants (mianserin and clomipramine) with placebo. Data were abstracted for the dichotomous outcome of symptom improvement in seven studies, and for the continuous variable of pain score in eight studies. The summary odds ratio for improvement with antidepressant therapy was 4.2 (95% confidence interval [CI]: 2.3 to 7.9), and the average standardized mean improvement in pain was equal to 0.9 SD units (95% CI: 0.6 to 1.2 SD units). On average 3.2 patients needed to be treated (95% CI: 2.1 to 6.5 patients) to improve 1 patient’s symptom. CONCLUSION: Treatment of functional gastrointestinal disorders with antidepressants appears to be effective. Whether this improvement is independent of an effect of treatment on depression needs further evaluation.